On Mon, Feb 7, 2022 at 9:16 PM Ilya Leoshkevich <iii@xxxxxxxxxxxxx> wrote:
>
> These macros are useful for both libbpf and bpf progs, so put them into
> a separate header dedicated to this use case.
>
> Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx>
> ---
> tools/lib/bpf/Makefile | 2 +-
> tools/lib/bpf/bpf_common_helpers.h | 30 ++++++++++++++++++++++++++
> tools/lib/bpf/bpf_helpers.h | 15 +------------
> tools/testing/selftests/bpf/bpf_util.h | 10 +--------
> 4 files changed, 33 insertions(+), 24 deletions(-)
> create mode 100644 tools/lib/bpf/bpf_common_helpers.h
>
> diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
> index b8b37fe76006..60b06c22e0a1 100644
> --- a/tools/lib/bpf/Makefile
> +++ b/tools/lib/bpf/Makefile
> @@ -239,7 +239,7 @@ install_lib: all_cmd
>
> SRC_HDRS := bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h xsk.h \
> bpf_helpers.h bpf_tracing.h bpf_endian.h bpf_core_read.h \
> - skel_internal.h libbpf_version.h
> + skel_internal.h libbpf_version.h bpf_common_helpers.h
Wait, how did we get from fixing s390x syscall arg fetching to
exposing a new public API header from libbpf?... I feel like I missed
a few revisions and discussion threads.
> GEN_HDRS := $(BPF_GENERATED)
>
> INSTALL_PFX := $(DESTDIR)$(prefix)/include/bpf
> diff --git a/tools/lib/bpf/bpf_common_helpers.h b/tools/lib/bpf/bpf_common_helpers.h
> new file mode 100644
> index 000000000000..79db303b6ae2
> --- /dev/null
> +++ b/tools/lib/bpf/bpf_common_helpers.h
> @@ -0,0 +1,30 @@
> +/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
> +#ifndef __BPF_COMMON_HELPERS__
> +#define __BPF_COMMON_HELPERS__
> +
> +/*
> + * Helper macros that can be used both by libbpf and bpf progs.
> + */
> +
> +#ifndef offsetof
> +#define offsetof(TYPE, MEMBER) ((unsigned long)&((TYPE *)0)->MEMBER)
> +#endif
> +
> +#ifndef sizeof_field
> +#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER))
> +#endif
> +
> +#ifndef offsetofend
> +#define offsetofend(TYPE, MEMBER) \
> + (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER))
> +#endif
> +
> +#ifndef container_of
> +#define container_of(ptr, type, member) \
> + ({ \
> + void *__mptr = (void *)(ptr); \
> + ((type *)(__mptr - offsetof(type, member))); \
> + })
> +#endif
> +
> +#endif
> diff --git a/tools/lib/bpf/bpf_helpers.h b/tools/lib/bpf/bpf_helpers.h
> index 44df982d2a5c..1e8b609c1000 100644
> --- a/tools/lib/bpf/bpf_helpers.h
> +++ b/tools/lib/bpf/bpf_helpers.h
> @@ -2,6 +2,7 @@
> #ifndef __BPF_HELPERS__
> #define __BPF_HELPERS__
>
> +#include "bpf_common_helpers.h"
> /*
> * Note that bpf programs need to include either
> * vmlinux.h (auto-generated from BTF) or linux/types.h
> @@ -61,20 +62,6 @@
> #define KERNEL_VERSION(a, b, c) (((a) << 16) + ((b) << 8) + ((c) > 255 ? 255 : (c)))
> #endif
>
> -/*
> - * Helper macros to manipulate data structures
> - */
> -#ifndef offsetof
> -#define offsetof(TYPE, MEMBER) ((unsigned long)&((TYPE *)0)->MEMBER)
> -#endif
> -#ifndef container_of
> -#define container_of(ptr, type, member) \
> - ({ \
> - void *__mptr = (void *)(ptr); \
> - ((type *)(__mptr - offsetof(type, member))); \
> - })
> -#endif
> -
> /*
> * Helper macro to throw a compilation error if __bpf_unreachable() gets
> * built into the resulting code. This works given BPF back end does not
> diff --git a/tools/testing/selftests/bpf/bpf_util.h b/tools/testing/selftests/bpf/bpf_util.h
> index a3352a64c067..bc0b741b1eef 100644
> --- a/tools/testing/selftests/bpf/bpf_util.h
> +++ b/tools/testing/selftests/bpf/bpf_util.h
> @@ -6,6 +6,7 @@
> #include <stdlib.h>
> #include <string.h>
> #include <errno.h>
> +#include <bpf/bpf_common_helpers.h>
> #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
>
> static inline unsigned int bpf_num_possible_cpus(void)
> @@ -31,13 +32,4 @@ static inline unsigned int bpf_num_possible_cpus(void)
> # define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
> #endif
>
> -#ifndef sizeof_field
> -#define sizeof_field(TYPE, MEMBER) sizeof((((TYPE *)0)->MEMBER))
> -#endif
> -
> -#ifndef offsetofend
> -#define offsetofend(TYPE, MEMBER) \
> - (offsetof(TYPE, MEMBER) + sizeof_field(TYPE, MEMBER))
> -#endif
> -
> #endif /* __BPF_UTIL__ */
> --
> 2.34.1
>
